Spark-plug.



J. DAYTON.

SPARK PLUG.

APPLIUATION FILED DB0. so, 1910.

Patented Aug. 22, 1911 UNITED STATES PATENT OFFICE.

JAMES M. DAYTON, OF TORRINGTON, CONNECTICUT, ASSIGNOR TO PROGRESSIVE MANU- FACTURING COMPANY, 0F TORRINGTON, CONNECTICUT, A CORPORATION OF CON- NECTICUT.

SPARK-PLUG.

Patented Aug'. 22, 1911.

Application led December 30, 1910. Serial No. 600,048.

To all whom it may cbncemr l Be it known that I, JAMES M. DAYTON, a citizen of the United States, residing at Torrington, in the county of Litchfield, State of Connecticut, have invented certain new` and-useful Improvements in Sparkllugs, ot' .which the following is a description, reference being had to the accompanying drawing and to the letters and figures of reference marked thereon.

My invention `relates to an improvement in spark plugs, particularl of the ty )e employed in what 1s termed t e jump spark or high tension system of ignition in gas en ines.

he object of the invention is to improve the constructiony of s ark plugs, and particularly of those Whic have a terminal cap fitting over the porcelain insulating tube or sleeve, said cap being in contact with the end of the center electrode.

The present invention consists in providing a spring terminal cap, in which' the ter-- minal cap is secured to the porcelain plug, and the upper rivet is headed over on the `inside ot' the cap, and engages a head' in the center electrode, a spring surrounding the rivet being interposed between the upper head thereof and a cupped washer, the spring holding the cupped washer against the terminal cap or the terminal clip interposed between the cupped washer and the ca i.

llhe invention is illustrated in the accompanying drawings, in wl1ich tl 1e figure reprcsents a sectional view of a spark plug, constructed in accordance with my invention.

A In this drawing, the body portion of the plug` is of any well known design, such as shown in my previous application for patent filed i\lovember 14th, 1910, or as herein illustrated, such as that shown in patentl to Mills, 825,850, of July 10th, 1906. In general, `it comprises a nipple or plug base A, an insu-- lating sleeve tube or plug B, prete 'ably ot' porcelain, through which passes the metal roll or stem C, forming the center electrode,

which is cemented therein.

D is the other elect rode, which is preferably oi.' wire and secured to the plug` buse 0r nipple, and E is the bushinv or stutling nut .sl-ruw, threaded into the base or nipple.

The porcelain plug has a recess or seat a in its upper end, in which rests the head I) olE the center electrode, this recess or seat being large enough to receive also the head on the lower end ot' the rivet or stud F, which head is inside ot' the terminal cap or lierrule (fl, which is preilerahly of brass pressed onto the porcelain, with its lower edge crimped into a recess in the porcelain.

A coiled spring I-I surrounds the rivet or stud F, at its upper end resting against the under side oi the outer head of said rivet, and at its lower end bearing' against a cupped washer c, which it keeps normally pressed against the face of the terminal cap G. Between the cupped washer and the face of the terminal cap, a terminal clip is adapted to be inserted and held by the pressure ot the spring.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

l. In a. spark plug, in combination with the insulating lug, the electrode passing therethrough, tie terminal cap u on said plug, a stud having its lower en riveted within the cap and engaging the electrode', whereby the cap is in electrical connection with the electrode, and a spring and washer carried on said stud, said s ring bearing at its lower eiid on said was 1er to normally kee i it in Contact with the face of the cap with a terminal clip interposed between the washer and the cap.

2. In a spark plug, in combination with the insulating plug, having a recess or seat; in its upper end, the electrode passing therethrough having a head located in said recess, a terminal cap or ferrule on said plug, a stud having its lower end riveted within the cap and located in said recess or seat in contact with the head oil the electrode, and a spring and washer' carried on said stud, said spring bearing at its lower end on said washer, to normallyI keep it `in contact with the face of the cap.

In testimony whereof I allxmy signature,

in presence oi two Witnesses.-

F. P. RYAN, E. J. Mums.

Copies of this patent may be obtained `for five cents each, by addressing the Commissioner of Pat-ents. Washington, D. G. 

